grade Nilai 1-100 (A,B,C,D,E)

uses crt;
var
   hasil:string;
   n:integer;
begin
   clrscr;
   write('nilai: ');readln(n);
   if n in[1..100] then
   begin
       if n in[1..20] then
          writeln('E')
       else if n in[21..40] then
          hasil:='D'
       else if n in[41..60] then
          hasil:='C'
       else if n in[61..80] then
          hasil:='B'
       else if n in[81-100] then
          hasil:='A'
       else
          hasil:=' Nilai anda tidak diantara 0-100';
   end;
   writeln('Kategori nilai anda: ',hasil);
   readln;
end.